1. Field of the Invention
This invention relates to the interstage storage of wafer blocks in plants for producing and processing wafer blocks.
2. Description of the Prior Art
Wafer blocks, sometimes called sweets blocks, are an intermediate product formed in the wafer or sweets industry. That intermediate product is made from fragile, crisp, brittle rectangular wafer sheets having a maximum moisture content of 1 to 4%, and in dependence on the production line is processed to form widely different wafer products or wafer-filled products.
The wafer sheets which are processed to form wafer blocks belong to the wafers of that kind which when they are still warm in an as-baked state and when they have been cooled to room temperature are crisp, brittle and fragile and which in the end product have a maximum moisture content of 1 to 4%. Examples of such fragile, brittle wafers made on an industrial scale are rectangular wafer sheets but also round wafer sheets, oblatelike wafers and other so-called flat wafers, also wafer plates, which in the wafer and sweets industries are described as low hollow wafers and consist of halves of hollow bodies, which halves are joined by flat webs to form large wafer plates and comprise nutlike, egglike, acornlike, cubelike and cylindrical shapes and the like, and cast hollow wafers, such as wafer cones, cast wafer cups, cast wafer figures and the like.
A difference must be made between such wafers and those which are made in the wafer industry and owing to their high sugar content (up to 35%), are plastically deformable in an as-baked or warm state and only after they have been cooled have a fragile, crisp, brittle consistency and in the end product have a moisture content up to 1 to 4%. Examples of said wafers made on an industrial scale are rolled wafer cones and wafer rolls, which are formed in that individual flat wafers or flat wafer cakes are rolled up in a warm, plastically deformable state and are then permitted to cool, or hollow rods or wafer rolls, which are made in that an endless, baked, thin wafer strip is helically wound in a plastically shapable state with overlapping convolutions on a cylindrical mandrel to form a tube, which is then cut to length and permitted to cool.
Wafers of another kind have as an end product a moisture content in excess of 8% and are baked from a wafer dough having a high egg content (10 to 50%) and are soft and elastic in an as-baked state and when they have been cooled to room temperature.
In the wafer industry the wafers of said kinds are produced and processed further in substantially automatic production lines, which in most cases are specialized for a single end product. In such a production line, which comprises an integrated plant for the production and further processing of wafer blocks, e.g., liquid wafer dough may be baked in a fully automatic baking machine, in most cases described as a wafer baking oven, to form large thin, rectangular brittle wafer sheets. The wafer sheets are taken from the wafer baking oven, cooled in a wafer sheet cooler and transported to a wafer sheet coating machine, in which they are coated with a whipped fat cream and are stacked to form cream-filled wafer blocks. The wafer blocks are subsequently cooled so that the cream is consolidated and the cohesion in each block is increased. The wafer blocks which have left the wafer block cooler are delivered to a wafer block cutting apparatus and are cut therein in two mutually orthogonal directions into parallelepipedic cream-filled wafers, which have the same size and are described as wafer bars or Neapolitan bars, and are subsequently airtightly packaged in packages of uniform size, e.g., 10 pieces per package.
Other production lines of the wafer industry are used to bake large rectangular (350 mm.times.750 mm) wafer sheets in automatic wafer baking ovens and in wafer-sheet coating machines are processed to form cream-filled wafer blocks as an intermediate product. Said wafer blocks are cut in wafer block cutting apparatuses into small parallelepipedic wafer pieces or wafer bars or wafers having the same size, which in a succeeding part of the production line are coated with chocolate or another coating composition and are subsequently packaged in packages of the same size.
In a production line designed for the production of chocolate bars filled with wafers or with wafer bars, large rectangular (350 mm.times.750 mm) wafer sheets are baked in an automatic wafer baking oven and in wafer sheet coating machines are processed to form an intermediate product consisting of cream-filled wafer blocks, which in wafer block cutting apparatuses are cut into small parallelepipedic wafer pieces or wafer bars or wafers and in a succeeding bar-forming plant are placed into molds for casting bars of chocolate and are thus integrated in the bars of chocolate to make bars of chocolate filled with wafers or wafer bars.
The wafer baking ovens or automatic wafer baking ovens which are arranged at the upstream end of such production lines or of those plant parts which serve for the production and further processing of wafer blocks include a multiplicity of identical wafer baking molds, which are arranged in respective baking tongs and provided each with two rectangular baking plates. Said modes are arranged in the wafer baking oven in a row, e.g., as an endless chain, and revolve in the wafer baking oven from a dough pouring station, in which liquid wafer dough is poured into the bottom baking plates of the opened baking tongs, through the baking space, in which the wafer sheets are baked in the closed baking tongs, to the wafer taking station, in which the wafer sheets are taken from the wafer baking oven. When the wafer baking oven has been started the chain of baking tongs revolves in an empty state and the oven is heated to the desired operating or baking temperature. Only when that temperature has been reached are the supply of dough to the dough pouring station and the pouring of wafer dough initiated. A wafer baking oven may comprise a chain of, e.g., 80 baking tongs and may be operated to bake each wafer sheet for 2 minutes. When the wafer baking oven is shut down, the supply of dough is first shut off and the chain of baking tongs is revolved further until the dough which has been poured for the last wafer sheet has completely been baked and has emerged in the wafer taking station. This means that a total of about 75 wafer sheets are baked after the supply of dough has been shut off. In the wafer sheet coating machine, 25 wafer blocks are made from said 75 wafer sheets. Each of said blocks consists of three wafer sheets and two layers of cream. Said wafer blocks must then be processed further in those plant parts of the production line which succeed the wafer sheet coating machine. When the wafer baking oven has been restarted and the baking temperature has again been reached and the supply of dough has again been initiated it will take about 2 minutes before the first completely baked wafer sheet can emerge from the wafer baking oven.
If the production must be interrupted for a relatively long time, e.g., for maintenance work or for an alteration of individual parts of the plant, it will be necessary to continue the operation of the wafer baking oven between the shut-off of the supply of dough and the re-initiation of the supply of dough and the oven must be kept at the operating or baking temperature during that time because otherwise the downtime will be prolonged by the time required to reheat the wafer baking oven. For this reason it has been usual to perform maintenance work or to effect alterations affecting those plant parts of the production line which succeed the wafer baking oven as far as possible during those times in which the production line is shut down for other reasons, e.g., in the evening hours after the end of production or during the weekend.
In order to minimize the loss of production which will result in a production line when a broken cutting wire of a wafer block cutting apparatus must be replaced or when the packaging film must be renewed or replaced in a wafer bar packaging machine, it is known to provide a wafer block accumulator, which is disposed between the wafer block cooling apparatus, which succeeds the wafer sheet coating machine, and those plant parts of the production line which succeed the wafer block cooling apparatus. When the wafer baking oven has been shut down such accumulator will permit an operation of those plant parts of the production plant which precede the wafer block cooling apparatus until such plant parts are empty. This is possible because the accumulator will receive the wafer blocks which have been formed and emerge from the wafer block cooling apparatus until said plant parts are empty.
In a known wafer block accumulator, a plurality of conveyor belts or storage belts are arranged one over the other and individual wafer blocks are stored in a row on said belts. Pivoted feed and delivery belts are provided, which in dependence on their angular position may serve any of the conveyor belts and serve to convey the wafer blocks to and from the storage belts. Because the pivotal movement of said feed and discharge belts must closely be limited owing to the low adhesion of the underside of each wafer block, an increase of the capacity can be achieved only in that the length of the storage belts and, as a result, the overall length of the entire wafer block accumulator, are increased.